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path: root/drivers/net/cxgb4vf/sge.c
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Diffstat (limited to 'drivers/net/cxgb4vf/sge.c')
-rw-r--r--drivers/net/cxgb4vf/sge.c122
1 files changed, 75 insertions, 47 deletions
diff --git a/drivers/net/cxgb4vf/sge.c b/drivers/net/cxgb4vf/sge.c
index f10864ddafb..ecf0770bf0f 100644
--- a/drivers/net/cxgb4vf/sge.c
+++ b/drivers/net/cxgb4vf/sge.c
@@ -154,13 +154,14 @@ enum {
*/
RX_COPY_THRES = 256,
RX_PULL_LEN = 128,
-};
-/*
- * Can't define this in the above enum because PKTSHIFT isn't a constant in
- * the VF Driver ...
- */
-#define RX_PKT_PULL_LEN (RX_PULL_LEN + PKTSHIFT)
+ /*
+ * Main body length for sk_buffs used for RX Ethernet packets with
+ * fragments. Should be >= RX_PULL_LEN but possibly bigger to give
+ * pskb_may_pull() some room.
+ */
+ RX_SKB_LEN = 512,
+};
/*
* Software state per TX descriptor.
@@ -1355,6 +1356,67 @@ out_free:
}
/**
+ * t4vf_pktgl_to_skb - build an sk_buff from a packet gather list
+ * @gl: the gather list
+ * @skb_len: size of sk_buff main body if it carries fragments
+ * @pull_len: amount of data to move to the sk_buff's main body
+ *
+ * Builds an sk_buff from the given packet gather list. Returns the
+ * sk_buff or %NULL if sk_buff allocation failed.
+ */
+struct sk_buff *t4vf_pktgl_to_skb(const struct pkt_gl *gl,
+ unsigned int skb_len, unsigned int pull_len)
+{
+ struct sk_buff *skb;
+ struct skb_shared_info *ssi;
+
+ /*
+ * If the ingress packet is small enough, allocate an skb large enough
+ * for all of the data and copy it inline. Otherwise, allocate an skb
+ * with enough room to pull in the header and reference the rest of
+ * the data via the skb fragment list.
+ *
+ * Below we rely on RX_COPY_THRES being less than the smallest Rx
+ * buff! size, which is expected since buffers are at least
+ * PAGE_SIZEd. In this case packets up to RX_COPY_THRES have only one
+ * fragment.
+ */
+ if (gl->tot_len <= RX_COPY_THRES) {
+ /* small packets have only one fragment */
+ skb = alloc_skb(gl->tot_len, GFP_ATOMIC);
+ if (unlikely(!skb))
+ goto out;
+ __skb_put(skb, gl->tot_len);
+ skb_copy_to_linear_data(skb, gl->va, gl->tot_len);
+ } else {
+ skb = alloc_skb(skb_len, GFP_ATOMIC);
+ if (unlikely(!skb))
+ goto out;
+ __skb_put(skb, pull_len);
+ skb_copy_to_linear_data(skb, gl->va, pull_len);
+
+ ssi = skb_shinfo(skb);
+ ssi->frags[0].page = gl->frags[0].page;
+ ssi->frags[0].page_offset = gl->frags[0].page_offset + pull_len;
+ ssi->frags[0].size = gl->frags[0].size - pull_len;
+ if (gl->nfrags > 1)
+ memcpy(&ssi->frags[1], &gl->frags[1],
+ (gl->nfrags-1) * sizeof(skb_frag_t));
+ ssi->nr_frags = gl->nfrags;
+
+ skb->len = gl->tot_len;
+ skb->data_len = skb->len - pull_len;
+ skb->truesize += skb->data_len;
+
+ /* Get a reference for the last page, we don't own it */
+ get_page(gl->frags[gl->nfrags - 1].page);
+ }
+
+out:
+ return skb;
+}
+
+/**
* t4vf_pktgl_free - free a packet gather list
* @gl: the gather list
*
@@ -1463,10 +1525,8 @@ int t4vf_ethrx_handler(struct sge_rspq *rspq, const __be64 *rsp,
{
struct sk_buff *skb;
struct port_info *pi;
- struct skb_shared_info *ssi;
const struct cpl_rx_pkt *pkt = (void *)&rsp[1];
bool csum_ok = pkt->csum_calc && !pkt->err_vec;
- unsigned int len = be16_to_cpu(pkt->len);
struct sge_eth_rxq *rxq = container_of(rspq, struct sge_eth_rxq, rspq);
/*
@@ -1481,42 +1541,14 @@ int t4vf_ethrx_handler(struct sge_rspq *rspq, const __be64 *rsp,
}
/*
- * If the ingress packet is small enough, allocate an skb large enough
- * for all of the data and copy it inline. Otherwise, allocate an skb
- * with enough room to pull in the header and reference the rest of
- * the data via the skb fragment list.
+ * Convert the Packet Gather List into an skb.
*/
- if (len <= RX_COPY_THRES) {
- /* small packets have only one fragment */
- skb = alloc_skb(gl->frags[0].size, GFP_ATOMIC);
- if (!skb)
- goto nomem;
- __skb_put(skb, gl->frags[0].size);
- skb_copy_to_linear_data(skb, gl->va, gl->frags[0].size);
- } else {
- skb = alloc_skb(RX_PKT_PULL_LEN, GFP_ATOMIC);
- if (!skb)
- goto nomem;
- __skb_put(skb, RX_PKT_PULL_LEN);
- skb_copy_to_linear_data(skb, gl->va, RX_PKT_PULL_LEN);
-
- ssi = skb_shinfo(skb);
- ssi->frags[0].page = gl->frags[0].page;
- ssi->frags[0].page_offset = (gl->frags[0].page_offset +
- RX_PKT_PULL_LEN);
- ssi->frags[0].size = gl->frags[0].size - RX_PKT_PULL_LEN;
- if (gl->nfrags > 1)
- memcpy(&ssi->frags[1], &gl->frags[1],
- (gl->nfrags-1) * sizeof(skb_frag_t));
- ssi->nr_frags = gl->nfrags;
- skb->len = len + PKTSHIFT;
- skb->data_len = skb->len - RX_PKT_PULL_LEN;
- skb->truesize += skb->data_len;
-
- /* Get a reference for the last page, we don't own it */
- get_page(gl->frags[gl->nfrags - 1].page);
+ skb = t4vf_pktgl_to_skb(gl, RX_SKB_LEN, RX_PULL_LEN);
+ if (unlikely(!skb)) {
+ t4vf_pktgl_free(gl);
+ rxq->stats.rx_drops++;
+ return 0;
}
-
__skb_pull(skb, PKTSHIFT);
skb->protocol = eth_type_trans(skb, rspq->netdev);
skb_record_rx_queue(skb, rspq->idx);
@@ -1549,11 +1581,6 @@ int t4vf_ethrx_handler(struct sge_rspq *rspq, const __be64 *rsp,
netif_receive_skb(skb);
return 0;
-
-nomem:
- t4vf_pktgl_free(gl);
- rxq->stats.rx_drops++;
- return 0;
}
/**
@@ -1679,6 +1706,7 @@ int process_responses(struct sge_rspq *rspq, int budget)
}
len = RSPD_LEN(len);
}
+ gl.tot_len = len;
/*
* Gather packet fragments.